Professor José-Alain Sahel with the wireless retinal implant.
The central vision in patients with geographic atrophy (GA), due to advanced age-related macular degeneration, has been restored with a wireless retinal implant, according to published results from an international, multicentre trial.
Of the 32 participants who completed 12 months of follow-up, 26 achieved clinically meaningful improvements in visual acuity, and 27 participants reported using the prosthetic vision system tested in the trial at home for reading numbers or words. On average, participants improved by 25 letters – about five lines – on a standard eye chart when using the device. Of all participants, 81% gained 10 or more letters.
The study was co-led by Professor José-Alain Sahel from University of Pittsburgh School of Medicine (UPMC), Professor Daniel Palanker from Stanford University, and Professor Frank Holz from the University of Bonn, Germany.
Prof Sahel said this was “the first time that any attempt at vision restoration has achieved such results in a large number of patients”.
“More than 80% of the patients were able to read letters and words, and some of them are reading pages in a book. This is really something we couldn’t have dreamed of when we started on this journey, together with Daniel Palanker, 15 years ago,” he said.
As AMD progresses, the centre of vision becomes increasingly blurry due to the irreversible damage to the light-sensing cells in the central part of the retina. In a healthy retina, those cells capture ambient light from the environment and transform it into pulses of electricity, which are then sent to nerve cells lining the back of the eye and, eventually, to the brain through the optic nerve.
we are investigating tricks that could further improve people’s quality of life and take them above the threshold for legal blindness
Prof Palanker’s PRIMA system replaces the lost photoreceptors with a 2×2 mm flexible wireless implant that converts light into electrical signals to stimulate remaining retinal cells. A camera mounted on specialised glasses captures images and projects them onto the implant using invisible near-infrared light. The implant then converts the light into electrical pulses, restoring the flow of visual information to the brain. Patients can adjust zoom and contrast settings to enhance functional vision.
The PRIMAvera trial enrolled 38 participants aged 60 and older at 17 sites across five European countries: France, Germany, Italy, the Netherlands, and the United Kingdom.
After one year of using the system, all procedure-related adverse events had subsided, and the majority of participants showed significant improvement in their ability to read letters on the eye chart. One participant improved by as many as 59 letters, or 10 lines.
“I don’t think we’ll ever be able to restore full 20/20 vision with the implant alone, but we are investigating tricks that could further improve people’s quality of life and take them above the threshold for legal blindness,” Sahel said. “One of the main requests we hear from patients is to be able to recognise faces and emotions again, and that’s something we’re working toward.”
Based on these results, the device manufacturer, Science Corporation, has applied for clinical use authorisation in Europe. UPMC was the first United States centre to implant the PRIMA device in 2020 in a study led by Joseph Martel, associate professor of ophthalmology, School of Medicine.
Other authors of the study include investigators at The Adolphe de Rothschild Foundation Hospital and The 15-20 National Eye Hospital, Paris; Moorfields Eye Hospital, London; and University of Rome Tor Vergata.
Reference
Holz FG, Le Mer Y, Sahel JA, et al. Subretinal photovoltaic implant to restore vision in geographic atrophy due to AMD. N Engl J Med 2025; doi: 10.1056/NEJMoa2501396.
